弱胶结软岩巷道断面形式及支护优化研究

Study on cross-section form and support optimization in weakly consolidated soft rock roadway

为研究弱胶结软岩巷道最佳断面结构形式及相应支护措施,以新疆伊犁四矿区弱胶结软岩巷道为工程背景,对巷道断面形式多样、支护措施难以确定的特殊工况进行探究。结合FLAC3D数值软件,分析复杂地质条件下不同断面形式及相应支护措施下弱胶结软岩巷道的围岩变形及塑性区发展规律。研究表明:弱胶结软岩巷道中不同断面形式的选取对巷道围岩变形及塑性区分布有较大影响,其中矩形巷道围岩变形最为严重;对比五种断面形式的围岩变形量及塑性区分布范围,选定马蹄形断面进一步分析不同支护措施下巷道围岩的变形特征及塑性区发展规律,并与现场监测结果对比分析,提出适用于弱胶结软岩巷道的支护方式,即"二次锚网喷+预应力锚索"支护。

In order to study the best form of cross-section structure and corresponding support measures in weakly consolidated soft rock roadway,based on the engineering background of weakly consolidated soft rock roadway of Yili No. 4Mine,the special working conditions was analyzed with various cross-section forms and difficulty in support measure determination. The paper used FLAC3 Dnumerical software to analyze the surrounding rock deformation and rock plastic zone distribution in weakly consolidated soft rock roadway under complicated geological conditions in different cross-section forms and corresponding support measures. The results show that different cross-section forms has great impact on the surrounding rock deformation and rock plastic zone distribution,and surrounding rock deformation of rectangular section is the largest. According to the comparison of the surrounding rock deformation amount and rock plastic zone distribution in five cross-sections,horseshoe section was selected for further analysis of surrounding rock deformation and rock plastic zone distribution under different support measures. The result was compared with site monitoring data,according to which a supporting measure was proposed for weakly consolidated soft rock roadway,applying secondary bolt-mesh-grouting and pre-stressed cable.